Abstract

The π electron cloud above and below the honeycomb structure of graphene causes each carbon atom to carry a permanent electric quadrupole moment which can attach any cation to impart interesting physical properties. We have synthesized Fe intercalated graphene structures to investigate tunable magnetic properties as a result of this chemical modification. An interesting antiferro quadrupolar ordering is observed which arises due to a coupling between magnetic dipole moment of Fe and electric quadrupole moment on graphenesurface. In contrast to antiferromagnetic Neel temperature (TN), here the ordering temperature (TQ) increases from 35.5 K to 47.5 K as the magnetic field is raised upto 1 Tesla.

Received 08 May 2013Accepted 13 July 2013Published online 25 July 2013

Acknowledgments:

AJA and AG acknowledge DST, New Delhi and CSIR respectively for awarding the fellowships during the work. DC thanks INSA, New Delhi for giving him a honorary scientist's position. SKS acknowledges DST, New Delhi, Govt. of India for financial support, Project No. SR/NM/NS-1089/2011.

[Magnets or magnetic bodies characterised by the
magnetic materials therefor; Selection of materials for their magnetic
properties, Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties]

Abstract

The π electron cloud above and below the honeycomb structure of graphene causes each carbon atom to carry a permanent electric quadrupole moment which can attach any cation to impart interesting physical properties. We have synthesized Fe intercalated graphene structures to investigate tunable magnetic properties as a result of this chemical modification. An interesting antiferro quadrupolar ordering is observed which arises due to a coupling between magnetic dipole moment of Fe and electric quadrupole moment on graphenesurface. In contrast to antiferromagnetic Neel temperature (TN), here the ordering temperature (TQ) increases from 35.5 K to 47.5 K as the magnetic field is raised upto 1 Tesla.